Guitar headstock



FIG. 1 is a top plan view of the guitar headstock showing my new design;

FIG. 2 is a side elevational view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a second side elevational view thereof, opposite the side shown in FIG. 2; and,

FIG. 5 is an end view thereof.

The broken lines shown in any views are to illustrate environment only, and form no part of the claimed design. 

The ornamental design for a guitar headstock, as shown and described. 